What a cookie banner can and cannot do

A cookie banner is only one part of a working consent system.

Inventory actual technologies

Inspect cookies, storage and network calls before and after consent. Separate strictly necessary operations from optional analytics or advertising where required.

Offer meaningful choices

For applicable regimes, refusal must work, choices should be understandable, and visitors need a usable way to withdraw or amend consent.

Test scripts before consent

A visually correct banner does nothing if optional tags execute before the relevant lawful basis exists. Confirm behavior using browser developer tools and representative regions.

Know publisher restrictions

Google requires eligible publishers serving personalized ads in the EEA, UK and Switzerland to use a Google-certified IAB TCF CMP. A homemade notice or code snippet does not automatically meet this requirement.

Further references

For European data rights, consult the European Commission guidance. For accessibility, consult W3C WAI evaluation guidance. For advertising consent, check your ad provider’s current publisher requirements.

• European Commission — data protection
• W3C WAI — accessibility evaluation
• Google AdSense — certified CMP requirements

Educational content, not legal advice. Last editorial review: 3 November 2026.